Rhyolite is made up of Quartz, Plagioclase, and Sanidine, with minor amounts of Hornblende and Biotite. It is a group of extrusive igneous rocks, rocks that formed from the solidification of molten rock material. Thick granitic lava that forms Rhyolite often cools quickly while pockets of gas are still trapped inside of the lava. The trapped gas is unable to escape, forming cavities known as "vugs" that often contain crystals, opal, or glassy material.
Also called mexican opal, mexican opal in rhyolite, mexican opal in rhyolite specimen, opal in rhyolite specimen, opal mexico
Opal in Rhyolite • 15.7 grams
SKU: 90100OP-15-7
$8.00 Regular Price
$4.00Sale Price
Opal in Rhyolite
- Mexico
- 15.7 grams ~ 49x25x12mm
- Natural
- 90100OP-15-7